German Patent Application No. A-37 21 279 describes a radio receiver which records traffic announcements in a digital speech memory upon receiving identifier signals which accompany the traffic messages. The identifier signals are known as announcement identifiers and once the traffic announcements are recorded, they are constantly available for playback. In this known radio receiver, only information received via a transmitter that is set to the receiver unit can be stored.
Moreover, car radios are known that have, for the sake of theft prevention, an operating part which can be removed from the car radio and which contains the operating elements of the car radio. When the user leaves the vehicle, the car radio is made unusable by removing the operating part since operation of the car radio without the associated operating elements is impossible.